A seal is needed in the oil and gas industry to withstand the high thermal and/or corrosive environment encountered in an oil and gas well operations, including natural and/or stimulated flow. Such a seal is needed on various well tools such as packers, expansion joints and subs. Presently, the existing elastomer compounds are not satisfactory to meet the requirements in many applications such as packing off and isolating the producing interval from the casing annulus. The existing elastomers do not withstand the in situ environments such as high temperatures, high pressure steam, high pressure sour corrosive (such as hydrogen sulfides and carbon dioxide) laden fluids, oil and gas, and salt water and associated chemicals, acids and inhibitors introduced. There are various materials that will solve one problem, but not all combinations. Any seal must have the property of being elastic so as to be able to seal off and hold against the encountered pressures, must be strong and rugged enough to withstand physical contact with well members without being torn or ruptured, and must be impervious and resistive to the various well fluids which are encountered.
The present invention is directed to an encapsulated polyelastic thermal and/or corrosive seal which can be used in a well environment, provide the necessary sealing, and maintain the seal in spite of the adverse variable environments to which it may be exposed.